CN103273423A - Grinding wheel grinding sound emission monitoring device - Google Patents
Grinding wheel grinding sound emission monitoring device Download PDFInfo
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- CN103273423A CN103273423A CN2013102497230A CN201310249723A CN103273423A CN 103273423 A CN103273423 A CN 103273423A CN 2013102497230 A CN2013102497230 A CN 2013102497230A CN 201310249723 A CN201310249723 A CN 201310249723A CN 103273423 A CN103273423 A CN 103273423A
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Abstract
The invention discloses a grinding wheel grinding sound emission monitoring device, and relates to a sound emission monitoring device. The grinding wheel grinding sound emission monitoring device comprises a locking flange, a magnetic rotation shaft, a shell, an annular magnetic pole, a permanent magnet, a magnetic slide plate, a limited block, an annular conical surface magnetic pole, a bevel gear, a handle, a retainer ring, a plug, an end cover, magnetorheological fluids, a sound emission sensor seat, a sound emission sensor and a detection circuit, the locking flange is locked with an external grinder grinding wheel, the left end of the magnetic rotation shaft is connected with the locking flange, the magnetic rotation shaft is provided with a hollow hole, the plug is arranged at an opening end of the hollow hole, the magnetorheological fluids are stored in the hollow hole, the hollow hole is communicated with the outer surface of the magnetic rotation shaft, the shell is sleeved on the magnetic rotation shaft, both the annular magnetic pole and the annular conical surface magnetic pole are positioned in the shell and are sleeved on the magnetic rotation shaft, the left end of the annular conical surface magnetic pole is connected with the magnetic slide plate, the left end of the magnetic slide plate is connected with the permanent magnet in a threaded manner, the right end of the annular conical surface magnetic pole is meshed with the bevel gear, and the detection circuit is arranged outside the shell and is electrically connected with the sound emission sensor.
Description
Technical field
The present invention relates to a kind of acoustic emission monitor(ing) device, especially relate to a kind of wheel grinding acoustic emission monitor(ing) device.
Background technology
Along with development of modern science and technology, all size high-performance optics surface has obtained in military and civilian each field widely using, existing manufacture level be difficult to satisfy this grow with each passing day qualitatively with quantitative demand.The low cost of high quality optical element is produced in batches has become the problem that the optics manufacturing industry presses for solution.
Diamond wheel grinding is the main processing mode of optical element, based on Dynamic Signal feature extraction and the recognition technology in the wheel grinding process, the grinding state is carried out on-line monitoring and control, is the effective way that improves the optical surface working (machining) efficiency.In the grinding process, the strain of the removal of emery wheel wear, workpiece material and emery wheel and workpiece etc. all can produce abundant acoustic emission signal, and acoustic emission signal is the dynamic process amount that can directly reflect that the wheel grinding state changes.The acoustic emission signal decay is serious, need try one's best near sound source in the installation site of sensor.And, comprise abundant information in the acoustic emission signal, bang path is very big to its influence, wave impedance between the bang path medium differs too conference and causes sensor can't obtain signal, the variation of sensor and sound source relative position and bang path, will make the acoustic emission signal of gathering lack comparativity, follow-up sound emission signal characteristic be extracted cause difficulty.
Grinding acoustic emission signal source is positioned at emery wheel and workpiece contact zone, not only sound source distance and bang path constantly change at workpiece and workbench calibrate AE sensor to be installed, and can be subjected to the interference of lathe miscellaneous part operational shock and contact-making surface friction, can't obtain true and reliable signal.Should try one's best near signal source in the calibrate AE sensor installation site, and relative position is fixed.The patent No. is that the utility model of CN96200753 proposes a kind of contactless liquid calibrate AE sensor structure, is installed on the cool but nozzle for liquid of lathe, utilizes fluid dielectric coolant to transmit acoustic emission signal.This device is subjected to the cooling condition restriction, can only be used for wet-milling processing, and the signal that collects can be subjected to the interference of coolant rate and pressure.Research work at present also has and the piezoelectricity calibrate AE sensor is installed in circumference of emery wheel carries out the grinding acoustic emission monitor(ing), and this mode can collect the acoustic emission signal of high s/n ratio, but needs to change grinding wheel structure, and versatility is relatively poor.(referring to document B.Varghese.In-process monitoring of truing using a sensor integrated diamond grinding wheel, Transactions of the North American Manufacturing Research Institute of SME, 2002:295-302.)
Summary of the invention
The object of the present invention is to provide a kind of wheel grinding acoustic emission monitor(ing) device simple in structure, as can to realize reliable wheel grinding acoustic emission signal collection.
The present invention is provided with locking flange, magnetic rotating shaft, housing, annular magnetic pole, permanent magnet, magnetic slideway dish, limited block, circular cone magnetic pole, bevel gear, handle, back-up ring, obstruction, end cap, magnetic flow liquid, calibrate AE sensor seat, calibrate AE sensor and testing circuit;
Described locking flange and the locking of outside grinder wheel, magnetic rotating shaft left end is connected with the locking flange, and the magnetic rotating shaft is provided with hollow hole, and the hollow hole openend is provided with obstruction, and hollow hole fills magnetic flow liquid, and hollow hole is communicated with by radial hole with magnetic rotating shaft outer surface; Housing is enclosed within the magnetic rotating shaft, and housing left end and magnetic rotating shaft are rotatably assorted, and housing right-hand member and back-up ring are connected, and shield ring sleeve is rotatably assorted in the magnetic rotating shaft and with the magnetic rotating shaft; Annular magnetic pole and circular cone magnetic pole are positioned at housing and all are sheathed in the magnetic rotating shaft, be equipped with magnetic flow liquid between annular magnetic pole centre bore and circular cone pole center hole and the magnetic rotating shaft outer surface and assemble the gap, circular cone magnetic pole left end is connected with magnetic slideway dish, the magnetic slideway is faced left to hold with permanent magnet and is spirally connected, circular cone magnetic pole right-hand member and bevel gear engagement, handle are located at bevel gear upward and are exposed housing; The calibrate AE sensor seat is located on the housing, and calibrate AE sensor is located in the calibrate AE sensor seat, and testing circuit is located at hull outside and is electrically connected with calibrate AE sensor.
Preferably be rotatably assorted by self-lubricating bearing between described housing left end and the magnetic rotating shaft; Preferably be rotatably assorted by self-lubricating bearing between described back-up ring and the magnetic rotating shaft.
Described permanent magnet preferably is made up of a plurality of permanent magnet blocks, and each permanent magnet blocks is pressed circumference uniform distribution on magnetic slideway dish, and each permanent magnet blocks is equipped with steel sole plate, and the steel sole plate bottom is provided with flat thread; Described magnetic slideway is faced left to hold and is provided with entad uniform radial slot, is provided with flat thread in the radial slot, and the steel sole plate of each permanent magnet blocks all is spirally connected by the flat thread in the radial slot of flat thread and magnetic slideway dish.
The centre bore of described annular magnetic pole and circular cone magnetic pole preferably is equipped with the tapered-body pole tooth.
Described calibrate AE sensor preferably adopts the piezoelectric type calibrate AE sensor.
Compare with existing acoustic emission monitor(ing) device, operation principle of the present invention and beneficial effect are as follows:
The present invention is installed in the grinder wheel axle head, at first be rotated counterclockwise bevel gear by handle, cooperate by flat thread, permanent magnet is moved apart from farthest, the center of circle, start makes the grinding wheel spindle rotation, the magnetic flow liquid that the hollow hole of magnetic rotating shaft is deposited is in the rotating shaft rotary course, because action of centrifugal force, along the gap between aperture arrival annular magnetic pole and the magnetic rotating shaft and the gap between circular cone magnetic pole and the magnetic rotating shaft.Then by the handle bevel gear that turns clockwise, when making permanent magnet arrive nearest home position, permanent magnet with annular magnetic pole and circular cone magnetic pole about two magnetic poles be bridge, the magnetic line of force forms closed magnetic loop by the gap between magnetic rotating shaft surface and magnetic rotating shaft and annular magnetic pole and the circular cone magnetic pole.Tapered-body pole tooth marginal portion magnetic flux maximum at the endoporus of two magnetic poles, assemble magnetic flow liquid, magnetic flow liquid surface in high-intensity magnetic field presents the crest phenomenon, tightly contact magnetic rotating shaft and annular magnetic pole and circular cone magnetic pole, the magnetic flow liquid that accumulates in utmost point tooth edge forms the magnetorheological ring of a series of " o " shape of twisted rotary shaft, makes to keep reliable liquid to contact between magnetic rotating shaft and magnetic pole.
The calibrate AE sensor of surface-coated couplant is pressed on surface of shell.Signaling path from the grinding area to the calibrate AE sensor is constant, and medium is solid or liquid, and solid and liquid wave impedance approach, and can effectively reduce wave reflection rate on the medium interface, reduce the decay of acoustic emission signal, improves signal to noise ratio.
This shows that the present invention has following outstanding advantage:
1, bang path is fixed.The present invention is installed in the grinding wheel spindle axle head, and is constant all the time with the grinding area relative position, compares to be installed on workbench or the anchor clamps, can effectively reduce the uncertainty that relative position constantly changes the sound emission signal characteristic that causes.
2, signal to noise ratio height.When permanent magnet during close home position, permanent magnet by annular magnetic pole and circular cone magnetic pole about two magnetic poles, make magnetic rotating shaft surface and and magnetic pole between gap location have stronger magnetic field, the design of the equidistant tapered-body pole tooth of magnetic pole bore area, making magnetic flow liquid be rule in the gap of magnetic rotating shaft and magnetic pole distributes, magnetic flow liquid presents surperficial crest phenomenon in high-intensity magnetic field, very high shear yield strength is arranged, thereby the magnetorheological ring of " o " shape that makes magnetic rotating shaft and magnetic pole distribute by a plurality of rules forms stable the contact, get rid of the gap between rotor and the stator, reduce because the reflection loss of the acoustic emission wave that transmission medium wave impedance difference causes.Simultaneously, device is selected the self-lubricating bearing support housing, and the noise that sliding friction is introduced between rotor and the stator is much smaller than roller bearings.
3, easy for installation.This device mainly is made up of two parts, at first will lock flange and substitute the original locking nut of lathe, installs and the locking emery wheel.The agent structure of constituent apparatus such as magnetic rotating shaft and housing, its flange end is connected by bolt with the locking flange, and contact-making surface is smeared couplant and is eliminated the contact-making surface space, reduces the reflection loss of acoustic emission signal.
4, easy to operate.Can change the permanent magnet radial position by knob, thereby change the magnetic field size, the flowability of control magnetic flow liquid.During low-intensity magnetic field, the magnetic flow liquid property that flows is good, opens end cap and obstruction, can add magnetic flow liquid very easily, replenishes loss, and can utilize centrifugal action to make it fully enter slit between magnetic rotating shaft and the magnetic pole.After forming high-intensity magnetic field, magnetic flow liquid viscosity increases, and having has very high shear yield strength, guarantees tight contact.
Description of drawings
Fig. 1 is the structural representation of the embodiment of the invention.
Fig. 2 is magnetic slideway dish and the magnet structure schematic diagram of the embodiment of the invention.
The specific embodiment
Referring to Fig. 1 and 2, the embodiment of the invention is provided with locking flange 1, magnetic rotating shaft 2, housing 3, annular magnetic pole 4,6 permanent magnet blocks 5, magnetic slideway dish 6, limited block 7, circular cone magnetic pole 8, bevel gear 9, handle 10, back-up ring 11, obstruction 14, end cap 15, magnetic flow liquid 16, calibrate AE sensor seat 18, calibrate AE sensor (not drawing among the figure) and testing circuits (not drawing among the figure).
Locking flange 1 and outside grinder wheel locking.Magnetic rotating shaft 2 left ends are connected with locking flange 1, and magnetic rotating shaft 2 is provided with hollow hole 21, and hollow hole 21 openends are provided with and stop up 14, and hollow hole 21 fills magnetic flow liquid, and hollow hole 21 is communicated with by 4 radial holes 22 with magnetic rotating shaft 2 outer surfaces.Housing 3 is enclosed within the magnetic rotating shaft 2, and housing 3 left ends and magnetic rotating shaft 2 are rotatably assorted by self-lubricating bearing 13, and housing 3 right-hand members and back-up ring 11 are connected, and back-up ring 11 is enclosed within the magnetic rotating shaft 2 and with magnetic rotating shaft 2 and is rotatably assorted by self-lubricating bearing 13; Annular magnetic pole 4 and circular cone magnetic pole 8 are positioned at housing 3 and all are sheathed in the magnetic rotating shaft 2, annular magnetic pole 4 centre bores and circular cone magnetic pole 8 centre bores are equipped with the tapered-body pole tooth, form magnetic flow liquid between tapered-body pole tooth and magnetic rotating shaft 2 outer surfaces and assemble gap (black is represented magnetic flow liquid among Fig. 1), circular cone magnetic pole 8 left ends are connected with magnetic slideway dish 6, magnetic slideway dish 6 left ends and 6 permanent magnet blocks 5 are spirally connected, each permanent magnet blocks 5 is pressed circumference uniform distribution on magnetic slideway dish 6, each permanent magnet blocks 5 is equipped with steel sole plate, and the steel sole plate bottom is provided with flat thread.Described magnetic slideway dish 6 left sides are provided with 6 entad uniform radial slots 61, be provided with flat thread in the radial slot 61, the steel sole plate of permanent magnet blocks 5 is installed in the radial slot 61, and the steel sole plate of permanent magnet blocks 5 all is spirally connected by the flat thread in the radial slot 61 of flat thread and magnetic slideway dish 6.The two ends of each radial slot 61 of magnetic slideway dish 6 are provided with limited block 7, and limited block 7 is connected as a single entity magnetic slideway dish 6 and circular cone magnetic pole 8, and limited block 7 is used for the spacing of permanent magnet blocks 5 radial displacements.Empty frame table among Fig. 2 shows that permanent magnet blocks 5 can move radially.
Circular cone magnetic pole 8 right-hand members and bevel gear 9 engagements, handle 10 is located on the bevel gear 9 and is exposed housing 3.Calibrate AE sensor seat 18 is located on the housing 3, and the piezoelectric type calibrate AE sensor is located in the calibrate AE sensor seat 18, and testing circuit is located at housing 3 outsides and is electrically connected with calibrate AE sensor.
Rotary handle 10 can rotate bevel gear 9, and makes 8 rotations of circular cone magnetic pole, thereby makes each permanent magnet blocks 5 synchronous radial motion.When turning clockwise, each permanent magnet blocks 5 is drawn close to the center of circle, counterclockwise then synchronously away from the center of circle.
In Fig. 1, mark 12 is that pad, 17 is the O RunddichtringO.
Claims (6)
1. a wheel grinding acoustic emission monitor(ing) device is characterized in that: be provided with locking flange, magnetic rotating shaft, housing, annular magnetic pole, permanent magnet, magnetic slideway dish, limited block, circular cone magnetic pole, bevel gear, handle, back-up ring, obstruction, end cap, magnetic flow liquid, calibrate AE sensor seat, calibrate AE sensor and testing circuit;
Locking flange and the locking of outside grinder wheel, magnetic rotating shaft left end is connected with the locking flange, and the magnetic rotating shaft is provided with hollow hole, and the hollow hole openend is provided with obstruction, and hollow hole fills magnetic flow liquid, and hollow hole is communicated with by radial hole with magnetic rotating shaft outer surface; Housing is enclosed within the magnetic rotating shaft, and housing left end and magnetic rotating shaft are rotatably assorted, and housing right-hand member and back-up ring are connected, and shield ring sleeve is rotatably assorted in the magnetic rotating shaft and with the magnetic rotating shaft; Annular magnetic pole and circular cone magnetic pole are positioned at housing and all are sheathed in the magnetic rotating shaft, be equipped with magnetic flow liquid between annular magnetic pole centre bore and circular cone pole center hole and the magnetic rotating shaft outer surface and assemble the gap, circular cone magnetic pole left end is connected with magnetic slideway dish, the magnetic slideway is faced left to hold with permanent magnet and is spirally connected, circular cone magnetic pole right-hand member and bevel gear engagement, handle are located at bevel gear upward and are exposed housing; The calibrate AE sensor seat is located on the housing, and calibrate AE sensor is located in the calibrate AE sensor seat, and testing circuit is located at hull outside and is electrically connected with calibrate AE sensor.
2. a kind of wheel grinding acoustic emission monitor(ing) device as claimed in claim 1 is characterized in that: all be rotatably assorted by self-lubricating bearing between described housing left end and the magnetic rotating shaft.
3. a kind of wheel grinding acoustic emission monitor(ing) device as claimed in claim 1 is characterized in that: be rotatably assorted by self-lubricating bearing between described back-up ring and the magnetic rotating shaft.
4. a kind of wheel grinding acoustic emission monitor(ing) device as claimed in claim 1, it is characterized in that: described permanent magnet is made up of a plurality of permanent magnet blocks, each permanent magnet blocks is pressed circumference uniform distribution on magnetic slideway dish, and each permanent magnet blocks is equipped with steel sole plate, and the steel sole plate bottom is provided with flat thread.
5. a kind of wheel grinding acoustic emission monitor(ing) device as claimed in claim 1, it is characterized in that: described magnetic slideway is faced left to hold and is provided with entad uniform radial slot, be provided with flat thread in the radial slot, all be spirally connected by the flat thread in the radial slot of flat thread and magnetic slideway dish at the bottom of the steel of each permanent magnet blocks.
6. a kind of wheel grinding acoustic emission monitor(ing) device as claimed in claim 1, it is characterized in that: the centre bore of described annular magnetic pole and circular cone magnetic pole is equipped with the tapered-body pole tooth.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310249723.0A CN103273423B (en) | 2013-06-21 | 2013-06-21 | Grinding wheel grinding sound emission monitoring device |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310249723.0A CN103273423B (en) | 2013-06-21 | 2013-06-21 | Grinding wheel grinding sound emission monitoring device |
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| Publication Number | Publication Date |
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| CN103273423A true CN103273423A (en) | 2013-09-04 |
| CN103273423B CN103273423B (en) | 2015-03-11 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201310249723.0A Expired - Fee Related CN103273423B (en) | 2013-06-21 | 2013-06-21 | Grinding wheel grinding sound emission monitoring device |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104772664A (en) * | 2015-04-30 | 2015-07-15 | 北京德铭纳精密机械有限公司 | Grinding device for PCD/CBN cutter |
| WO2020073713A1 (en) * | 2018-10-11 | 2020-04-16 | 长沙理工大学 | Single-point diamond trimming grinding wheel device based on on-line monitoring of acoustic emission |
| TWI745455B (en) * | 2016-10-26 | 2021-11-11 | 日商喜基雅精機製作所股份有限公司 | Grinder |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19826422A1 (en) * | 1998-06-05 | 1999-12-09 | Bernd Woop | Combined sensor system for rail vehicle wheels |
| US6615149B1 (en) * | 1998-12-10 | 2003-09-02 | Rosemount Inc. | Spectral diagnostics in a magnetic flow meter |
| CN102410847A (en) * | 2010-08-11 | 2012-04-11 | 罗斯蒙德公司 | Noise detection and avoidance |
| CN103090959A (en) * | 2013-02-27 | 2013-05-08 | 重庆绿色智能技术研究院 | Acoustic velocity measurement method and device of magnetorheological fluid ultrasonic wave |
-
2013
- 2013-06-21 CN CN201310249723.0A patent/CN103273423B/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19826422A1 (en) * | 1998-06-05 | 1999-12-09 | Bernd Woop | Combined sensor system for rail vehicle wheels |
| US6615149B1 (en) * | 1998-12-10 | 2003-09-02 | Rosemount Inc. | Spectral diagnostics in a magnetic flow meter |
| CN102410847A (en) * | 2010-08-11 | 2012-04-11 | 罗斯蒙德公司 | Noise detection and avoidance |
| CN103090959A (en) * | 2013-02-27 | 2013-05-08 | 重庆绿色智能技术研究院 | Acoustic velocity measurement method and device of magnetorheological fluid ultrasonic wave |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104772664A (en) * | 2015-04-30 | 2015-07-15 | 北京德铭纳精密机械有限公司 | Grinding device for PCD/CBN cutter |
| TWI745455B (en) * | 2016-10-26 | 2021-11-11 | 日商喜基雅精機製作所股份有限公司 | Grinder |
| WO2020073713A1 (en) * | 2018-10-11 | 2020-04-16 | 长沙理工大学 | Single-point diamond trimming grinding wheel device based on on-line monitoring of acoustic emission |
| US10836011B2 (en) | 2018-10-11 | 2020-11-17 | Changsha University Of Science And Technology | Single-point diamond dresser for grinding wheel based on acoustic emission online monitoring |
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| CN103273423B (en) | 2015-03-11 |
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Granted publication date: 20150311 Termination date: 20210621 |